One of the major difficulties in investigating the relationship between life stress and cancer has been the definition and measurement of stress. In this project an interview-based, standardized measure of stress will be compared with a more traditional self-report life events checklist, and the associations between life stress and the severity of disease will be examined in a sample of breast cancer patients. The aims of this 2 year pilot project are to 1) develop collaborative relationships with local oncology clinics and practices in Eugene and Portland, OR, 2) establish a recruitment base of women with breast cancer in Western Oregon, 3) recruit a sample of 60 women with primary breast cancer to participate in a study on the associations between life stress and the severity of their disease at diagnosis, and 4) identify specific features of life stress, social support, and coping which may be critical to our understanding of the relationship between life stress and the progression of breast cancer. Participants will be recruited within one year of their diagnosis of breast cancer through medical centers. They will be sent a packet of questionnaires asking about life stress, social support and coping during the year preceding their diagnosis. They will then be interviewed in their homes using a semi-structured interview designed to tap 10 major areas of life experiences. The information from the interview will then be rated by trained Life Events and Difficulties (LEDS) raters, yielding interview-based assessments of life stress, social support and coping. Medical cancer history regarding the diagnosis and severity of disease will be collected during the interview and verified by chart review. This study is exploratory and will begin to clarify the nature of associations between stress and cancer progression, ultimately guiding the development of psychosocial and stress management interventions.